Container system



Feb. 7, 1961 D. H. BAUGHAN CONTAINER SYSTEM 3 Sheets-Sheet 1 Filed OC'S.24, 1957 1N VENTOR Drury H. Baughan I l /O BY W ATTORNEY 5 Fel 7, 1961D. H. BAUGHAN 2,970,736

' CONTAINER SYSTEM Filed Oct. 24, 1957 3 Sheets-Sheet 2 /Il 9" H I f/6 Wl INVENTOR Drury H. Haug/van ATTORNEYS Feb. 7, 1961 D. H. BAUGHAN2,970,736

CONTAINER SYSTEM Filed Oct. 24, 1957 3 Sheets-Sheet 3 fik" INVENTORDrury. H.- Haug/mn BY 1%wv ATTORNEY United States Patent C CONTAINERSYSTEM Drury H. Baughan, Richmond, Va., assignor to Reynolds MetalsCompany, Richmond, Va., a corporation of Delaware Filed oci. 24, 1957,ser. No. 692,092

s Claims. (ci. 229-35) This invention relates to a moistureproofcontainer for use in the freezing, storing and heating of food products.

Heretofore, containers have been used which employ a very thin metalfoil, such as tin or aluminum foil, as a moisture impervious barrier outhe inner or outer surface of a fibrous container wall. While such foilis generally impervious to moisture, it is normally rolled so thin as tocontain many pinholes which render such containers ineffective toprevent food deterioration by reason of infiltration of moisture bearingair. Other disadvantages of conventional containers of this type are thedifculties involved in obtaining leakproof joints or seals between thecarton walls and closures, and the use of wax bearing sealing materialswhich render the container useless for heating of the food storedtherein.

It is a principal object of this invention to provide a foil containerso constructed as to obviate the difficulties mentioned and which isuseful for freezing, storing and heating food products, such as fruits,berries, fruit juice concentrates, soups, beverages, vegetables and thelike.

It is a further object of the invention to provide a single foil layercontainer which is rendered impervious to hot or cold liquids byapplication of a layer of thermoplastic material, bonded thereto or to afibrous liner, which remains set and hard under normal temperatures ofusage but softens under application of heat and pressure, duringfabrication of the container, to seal the' wall edges to the closures.

It is another object of the invention to provide an irnproved containerconstruction which utilizes a minimum of material yet is rigid anddurable. A

Yet another object of the invention lies in the provision of an openerstrip of strong and durable material, preferably heat bonded to thecontainer closure, which enables the container to be readily and quicklyopened for removal of its contents, such strip serving to break theclosure seal and pull the entire closure from the container.

The novel features that are considered characteristic of the inventionare set forth with particularity in the appended claims. The inventionitself, however, both as to its organization and its method ofoperation, together with additional objects and advantages thereof, willbest be understood from the following description of specic embodimentswhen read in connection with the accompanying drawings, wherein likereference characters indicate like parts throughout the several figuresand in which:

Figure 1 is a perspective view of a container constructed in accordancewith the invention;

Figure 2 is an enlarged vertical longitudinal sectional view taken online 2 2 of Fig. l showing the wall and closure sections in exaggerateddetail;

Figure 3 is a top plan view of the container side Wall precut to sizeand ready for forming;

Figure 4 is a perspective view of the containerwall formed to shapeprior to insertion of the end closures;

Patented Feb. 7, 1961 Figure 5 is a top plan view of a container closureprecut to size and ready for forming;

Figure 6 is a top plan view of the closure partially formed;

Figure 7 is a view similar to Fig. 6 showing the closure after thecorners are completely folded;

Figure 8 is a perspective view of the inverted lower end of thecontainer with the bottom closure inserted prior to sealing of thecontainer wall to the closure;

Figure 9 is a partial side elevation of one end of the container showingthe positioning of forming blocks to apply heat and pressure for sealinga closure thereto;

Figure 10 is a top plan view, before forming, of a modified closureembodying a removal strip;

Figure l1 is an enlarged detail section taken on line lll-11 of Fig. l0;

Figure l2 is a top plan view of the modified closure formed and readyfor insertion into the container;

Figure 13 is a side elevation of the closure shown in Fig. 11;

Figure 14 is a perspective view of the upper end of the container withthe modified closure of Fig. 12 inserted and sealed in place, and

Figure 15 is an enlarged detail section taken on line 15-15 of Fig. 14.

Referring now to the drawing, specifically to Fig. 1, the containerillustrated is a preferred embodiment of the invention and comprises atubular side wall'W of rectangular section closed at both ends byidentical closure members E. The wall W is formed of a single sheet 1(Fig. 3) of laminated construction (Fig. 2) and comprises an outer layer3 of metal foil, such as aluminum or tin, preferably coated on a thinlayer 4 of fibrous material such as paperboard, and further sealed withan inner coating 5 of a thermoplastic material, such as polythene orpolyethylene.

All three layers of the side wall sheet 1 are very thin, their thicknessbeing greatly exaggerated in Fig. 2 for clarity of illustration. Thefoil outer layer and the plastic inner layer are both impervious toliquids, the inner layer serving to seal any pinholes which may exist inthe foil. In certain instances, as where rigidity is unessential, it maybe desirable to omit the intermediate layer and use only foil coatedwith the thermoplastic as the container wall.

Each end closure E is also preferably formed of a single laminated sheet2 (Fig. 5), which, as best shown in Fig. 2, comprises a layer of metalfoil 6 coated on both sides by layers 7 and 8 of thermoplastic materialsuch as polyethylene. Each closure is formed with a peripheralout-turned ange 9 over which the respective end portions l0 of the sideWallis folded 180. Heat and pressure is then applied to seal theperipheral joints resulting in the bonding of the inner wall layer 5 toboth thermoplastic layers 7 and S of the closures 2. It will be notedthat this structure provides contacting thermoplastic layers at all edgeseals, the surface layers 7 and 8 of the end closure engaging the innerlayer 5 of the wall so that when heated, these layers become integraland form a strong, fluid tight seal that has great strength.

Figs. 3-9 illustrate a preferred method of fabricating the container.The described laminated sheet 1 of wall material is cut to apredetermined size, as shown in Fig. 3. Fold lines 11 are scored atfixed distances from the top and bottom edges and parallel thereto andto each other to form the end fold portions 10. Fold lines l2 are formedat fixed distances from the side edges to form around a mandrel to anydesired shape, round, square, hexagonal or the like, the rectangularshape being illustrated in Fig. 4. The fin 14 is then folded to lieflush against the wall body. A

Each closure E is also precut to size, see Fig. 5, from the laminatedsheet material 2, previously described. A pair of parallel fold lines 1Sare scored on the sheet at equal distances from the upper and loweredges, respectively, and a second pair of parallel fold lines 16 aremarked at the same distance from the side edges to define the portionsforming the il'ange 9. Diagonal fold lines 17 are marked from theintersections of the two sets of parallel lines 15 and 16 to the cornersof the sheet. The peripheral iiange 9 turned 90 to the sheet is thenformed by folding along the lines 15 and 16, the excess material at thecorners of the rectangle being folded along lines 17 to provideprojecting tabs 17', see Fig. 6. The tabs 17 are then folded by pressureto lie along two or more sides of the peripheral ange 9, as shown inFig. 7.

A formed bottom closure E is then inserted into container wall W untilthe outer edge of flange 9 is approximately even with 'fold line il, seeFig. 8. It is tacked here by a quick application of heat which bondsthermoplastic layers and S at a number of spaced points. The end fold ofthe side wall is then folded 180 over the closure flange 9 along foldline 11, this fold lil binding the fin 14 iiat against the wall. Apredetermined amount of heat and pressure is then applied simultaneouslyto the inside and outside of fold 1) by means of suitable heatedpressure forms, one of which enters the container to the level of theclosure E inside fold 10.

Figure 9 illustrates such a heated forming block 13 seated within fold10 at the end or the container. Two lateral forming blocks 19 and 20exert pressure and heat on two side walls of the container opposite thefold 10 to seal the Walls and fold to both sides of the closure flange9. The container may be removed, turned 90, and reinserted between theforming blocks to seal the remaining two sides of fold 10, or additionalforming blocks may be used to simultaneously seal all sides. After thecontainer is filled with the liquid or solid food to be packaged, theupper end is closed and sealed by an upper closure E, formed, appliedand sealed in the same manner. A similar method of fabrication, withsome differences in detail, may be used to form round, square,hexagonal, conical or other shaped containers.

A modified and readily removable closure E is illustrated in Figs.10-15. The closure E may be formed of a precut sheet 2 exactly asdescribed and shown in Figure 5. Before forming, however, a removalstrip or tape 21 of thin material having high strength is placed underthe closure sheet 2. This strip 21 is provided with surface layers of aheat sealing medium compatible with the heat sealing surface S of thecontainer wall and preferably, but not necessarily, is heat bonded tothe closure sheet 2. The strip 21 extends beyond the ends of the closureproper to form pull tabs 22 and 23. The removal strip is of laminatedstructure whose layers may vary in material so long as a very strong,durable member is provided.

Very good results have been obtained by forming one of the layers of thestrip 2 of the polyethylene terephthalate resin sold under the tradename Mylar which is outstandingly strong and chemically formed withoriented molecules of high tensile strength similar to DacronfPreferably, as shown in Fig. ll, the strip comprises an intermediatelayer of metal foil coated on opposite sides with thermoplastic layers24 and 26, one of which may be Mylar and the other a thermoplastic suchas polyethylene. in a preferred embodiment, the layer 24 may be Mylarand the layer 26 may be Saran which is a generic class of thermoplasticresins formed by polymerization of vinyl chloride or polyvinylidenechloride.

Figures 12 and 13 are top and elevational views, respectively, of theclosure E' completely formed with the removal strip 21 attached and itspull tabs 22 and 23 extending from the ends of the closure. The closureE' is inserted into the tubular container wall W and heat sealed theretoin the same manner as previously described, except that portions of thetabs 22 and 23 are folded over closure ange 9 and under Wall fold 10,see Figure 15, and are heat sealed to both of these upon application ofthe heat and pressure means. The ends of tabs 22 and 23 lie unsealed,however, adjacent the outside layer 7 of closure E'. This may beaccomplished in any suitable manner, as for example, by varying theshape of the inserted heat and pressure form 18 to insure that heat isnot applied to the ends of tabs 22 and 23.

Opening of the container illustrated in Figure 14 is eiected by pullingeither tab 22 or 23 toward the other. Removal strip 21 is suicientlystrong to break the seal between ange 9 of the closure and fold 10 ofthe container wall and has the unique advantage of lifting the entireend closure from the container even when the package is frozen. This isparticularly advantageous when the thermoplastic sealing layers havebeen somewhat softened by heating or cooking the food content in thecarton. The complete removal of the end closure enables rapid access tocontents of the container without requiring use of tools.

The advantages of the invention are quite apparent from the foregoingdescription. The primary advantage resides in the fact that a exible,light weight carton is provided of thin laminated sheet material whichis as eiective in protecting its contents from air and moisture as is aheavy sealed, more expensive metal can. The container is of simpleconstruction capable of fabrication on conventional machines. Althoughthe material is thin and llexible, the sealed folds in the Wall andclosure members provide an adequate amount of rigidity so that a liquidfilled container can be dropped without material damage to the carton orloss of contents. The foil layer on the outside of the carton provideseye appeal and the provision of a removal strip permits ready access tothe food content without the need for puncturing the carton with a canopener or sharp tool. Finally, and outstandingly, the doublethermoplastic layers of the end closure engaging the inner thermoplasticlayers of the wall, enables the integral joining of these layers to forma completely duid-tight seal.

Although certain specic embodiments of the invention have been shown anddescribed, it is obvious that many modications thereof are possible. Theinvention, therefore, is not to be restricted except insofar as isnecessitated by the prior art and by the spirit of the appended claims.

What is claimed and desired to be secured by Letters Patent is:

1. A liquid impervious container for freezing, storing, and heating offoods comprising: a laminated tubular side wall having an outer layer ofmetal foil bonded to an inner layer of thermoplastic material; alaminated end closure telescoped into said tubular side wall andcomprising a layer of foil and a layer of thermoplastic material bondedto each side thereof, said closure having a central hat portion and anoutwardly turned peripheral flange, said side wall having a fold oversaid flange, and both layers of thermoplastic material of the closurebeing heat bonded to the thermoplastic layer of the container side wallat the said fold; and a closure removal strip adjacent the inner side ofsaid end closure and extending outwardly thereof, said removal stripcompricing laminations of thermoplastic materials bonded on each side ofa foil layer, one of said laminations comprising a strong durablematerial whereby the exertion of pulling force on an end of said stripwill serve to break the seal between the closure and side wall to openthe container.

2. A container as set forth in claim 1 wherein said removal strip isheat bonded to the inner side of the end closure and comprises a layerof Mylar, a layer of foil, and a layer of Saran bonded together.

3. A liquid impervious container for freezing, storing, and heating offoods comprising: a laminated tubular side wall having an outer layer ofmetal foil bonded to an inner layer of thermoplastic material; aAlaminated end closure telescoped into said tubular side wall andcomprising a layer of foil and a layer of thermoplastic material bondedto each side thereof, said closure lhaving a central dat portion and anoutwardly turned peripheral ange, said side wall having a fold over saidflange, and

both layers of thermoplastic material of the closure being heat bondedto the thermoplastic layer of the container side wall at the said fold;and a closure removal strip adjacent the inner side of said end closureand extending outwardly thereof, whereby the exertion cf pulling forceon the ends of said strip will serve to break the seal between theclosure and side wall and accomplish intact removal of the end closure.

References Cited in the tile of this patent UNITED STATES PATENTS1,462,443 Brooks July 17, 1923 2,100,739 Gilllan Nov. 30, 1937 2,150,058Frazier May 7, 1939 2,152,322 Moore Mar. 28, 1939 2,152,323 Moore Mar.28, 1939 2,437,114 Moore Mar. 2, 1948 2,603,401 Strauss July 15, 19522,665,616 Jungmayr Jan. 12, 1954 2,808,192 Raisin Oct. 1, 1957 2,829,701Keely Apr. 8, 1958 FOREIGN PATENTS 7570A Great Britain of

